Organic light-emitting display apparatus and method of manufacturing the same

ABSTRACT

An organic light-emitting display apparatus includes a substrate, thin film transistors (TFTs), and organic light-emitting diode elements (OLEDs). First wirings have a first width and a first height and second wirings have a second width and a second height, in which the first wirings and the second wirings are formed in at least a portion of areas between the OLEDs. Third wirings connect the first wirings and the second wirings and have a third width smaller than the first width of the first wirings and the second width of the second wirings or have a third height smaller than the first height of the first wirings and the second height of the second wirings. An insulating layer covers at least a portion of the first and second wiring portions and exposes at least a portion of the third wirings.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from and the benefit of Korean PatentApplication No. 10-2014-0183305, filed on Dec. 18, 2014, which is herebyincorporated by reference for all purposes as if fully set forth herein.

BACKGROUND

1. Field

Exemplary embodiments relate to an organic light-emitting displayapparatus and a method of manufacturing the same.

2. Discussion of the Background

Organic light-emitting display devices can provide features such as awide is viewing angle, high contrast ratio, and rapid response time.

In general, organic light-emitting display devices can be manufacturedby forming thin film transistors (TFTs) and organic light-emitting diodeelements (OLEDs) on a substrate. The OLEDs are self-emitting units.Organic light-emitting display devices can be used as display units insmall devices such as cellular phones or in large devices such as TVs.

Organic light-emitting display devices may include pixels (andsub-pixels), in which each pixel is an OLED including an intermediatelayer that includes an emission layer (EML) and is disposed between apixel electrode and an opposite electrode. The pixel may be controlledto emit light and adjust the light emission intensity thereof via a TFTthat is electrically connected to the pixel electrode. The oppositeelectrode may be integrally formed with a plurality of pixels(sub-pixels).

The above information disclosed in this Background section is only forenhancement of understanding of the background of the inventive concept,and, therefore, it may contain information that does not form the priorart that is already known in this country to a person of ordinary skillin the art.

SUMMARY

Exemplary embodiments may provide a large-sized organic light-emittingdisplay device for displaying a high quality image by reducing IR dropin an integrally formed (e.g. being formed on an entire surface of adisplay area) opposite electrode.

Additional aspects will be set forth in the detailed description whichfollows, and, in part, will be apparent from the disclosure, or may belearned by practice of the inventive concept.

According to one or more exemplary embodiments, an organiclight-emitting display apparatus includes a substrate, thin filmtransistors (TFTs) and organic light-emitting diode elements(OLEDs) onthe substrate, the TFTs being electrically connected to the OLEDs, firstwirings having a first width and a first height and second wiringshaving a second width and a second height, wherein the first wirings andthe second wirings are formed in at least a portion of areas between theOLEDs, third wirings connecting the first wirings and the second wiringsand having a third width smaller than the first width of the firstwirings and the second width of the second wirings or having a thirdheight smaller than the first height of the first wirings and the secondheight of the second wirings, and an insulating layer covering at leasta portion of the first wirings and the second wirings and comprisingopenings that expose the third wirings.

According to one or more exemplary embodiments, an organiclight-emitting display apparatus includes a substrate; a first thin filmtransistor (TFT) and a first organic light-emitting diode element (OLED)on the substrate, the first TFT being electrically connected to thefirst OLED; a second TFT and a second OLED on the substrate, the secondTFT being electrically connected to the second OLED; a third TFT and athird OLED on the substrate, the third TFT being electrically connectedto the third OLED; a first wiring having a first width and a firstheight, wherein the first wiring is disposed in at least a portion of anarea between the first and second OLEDs; a second wiring having a secondwidth and a second height, wherein the second wiring is disposed in atleast a portion of an area between the second and third OLEDs; a thirdwiring connecting the first wiring and the second wiring and having atleast one of (a) a third width smaller than the first width of the firstwiring and the second width of the second wiring and (b) a third heightsmaller than the first height of the first wiring and the second heightof the second wiring; and an insulating layer covering at least aportion of the first wiring and the second wiring and comprising anopening that exposes at least a portion of the third wiring.

According to one or more exemplary embodiments, a method ofmanufacturing an organic light-emitting display apparatus includespreparing a substrate, forming a plurality of pixel electrodes on thesubstrate, forming, in at least a portion of areas between the pixelelectrodes, a plurality of first wirings having a first width and afirst height and a plurality of second wirings having a second width anda second height, forming a plurality of third wirings that connect thefirst wirings and the second wirings and have a third width smaller thanthe first width of the first wirings and the second width of the secondwirings or have a third height smaller than the first height of thefirst wirings and the second height of the second wirings, forming aninsulating layer that have a plurality of first openings to expose acentral portion of each of the pixel electrodes and a plurality ofsecond openings to expose the third wirings, forming a common layer onan entire surface of the insulating layer and on the first, secondopenings, removing the common layer formed on the third wirings exposedthrough the second openings in the insulating layer by applying avoltage to the first and second wirings, and forming an oppositeelectrode on the common layer such that the opposite electrode directlycontacts the third wirings exposed through the second openings of theinsulating layer.

The foregoing general description and the following detailed descriptionare exemplary and explanatory and are intended to provide furtherexplanation of the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the inventive concept, and are incorporated in andconstitute a part of this specification, illustrate exemplaryembodiments of the inventive concept, and, together with thedescription, serve to explain principles of the inventive concept.

FIG. 1 is a plan view schematically illustrating an organiclight-emitting display apparatus according to an exemplary embodiment;

FIG. 2 is a cross-sectional view illustrating an organic light-emittingdisplay apparatus cut along the lines II-II′ of FIG. 1;

FIG. 3 is an enlarged plan view illustrating a portion III of theorganic light-emitting display apparatus of FIG. 1;

FIG. 4 is a cross-sectional view illustrating an organic light-emittingdisplay apparatus cut along the lines IV-IV′ of FIG. 3;

FIGS. 5 through 7 are cross-sectional view schematically illustrating amethod of manufacturing an organic light-emitting display apparatus,according to an exemplary embodiment; and

FIG. 8 is a plan view schematically illustrating a display area of theorganic light-emitting display apparatus according to an exemplaryembodiment.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of various exemplary embodiments. It is apparent, however,that various exemplary embodiments may be practiced without thesespecific details or with one or more equivalent arrangements. In otherinstances, well-known structures and devices are shown in block diagramform in order to avoid unnecessarily obscuring various exemplaryembodiments.

In the accompanying figures, the size and relative sizes of layers,films, panels, regions, etc., may be exaggerated for clarity anddescriptive purposes. Also, like reference numerals denote likeelements.

When an element or layer is referred to as being “on,” “connected to,”or “coupled to” another element or layer, it may be directly on,connected to, or coupled to the other element or layer or interveningelements or layers may be present. When, however, an element or layer isreferred to as being “directly on,” “directly connected to,” or“directly coupled to” another element or layer, there are no interveningelements or layers present. For the purposes of this disclosure, “atleast one of X, Y, and Z” and “at least one selected from the groupconsisting of X, Y, and Z” may be construed as X only, Y only, Z only,or any combination of two or more of X, Y, and Z, such as, for instance,XYZ, XYY, YZ, and ZZ. Like numbers refer to like elements throughout. Asused herein, the term “and/or” includes any and all combinations of oneor more of the associated listed items.

Although the terms first, second, etc. may be used herein to describevarious elements, components, regions, layers, and/or sections, theseelements, components, regions, layers, and/or sections should not belimited by these terms. These terms are used to distinguish one element,component, region, layer, and/or section from another element,component, region, layer, and/or section. Thus, a first element,component, region, layer, and/or section discussed below could be termeda second element, component, region, layer, and/or section withoutdeparting from the teachings of the present disclosure.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper,” and the like, may be used herein for descriptive purposes, and,thereby, to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the drawings. Spatiallyrelative terms are intended to encompass different orientations of anapparatus in use, operation, and/or manufacture in addition to theorientation depicted in the drawings. For example, if the apparatus inthe drawings is turned over, elements described as “below” or “beneath”other elements or features would then be oriented “above” the otherelements or features. Thus, the exemplary term “below” can encompassboth an orientation of above and below. Furthermore, the apparatus maybe otherwise oriented (e.g., rotated 90 degrees or at otherorientations), and, as such, the spatially relative descriptors usedherein interpreted accordingly.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting. As used herein, thesingular forms, “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. Moreover,the terms “comprises,” comprising,” “includes,” and/or “including,” whenused in this specification, specify the presence of stated features,integers, steps, operations, elements, components, and/or groupsthereof, but do not preclude the presence or addition of one or moreother features, integers, steps, operations, elements, components,and/or groups thereof

Various exemplary embodiments are described herein with reference tosectional illustrations that are schematic illustrations of idealizedexemplary embodiments and/or intermediate structures. As such,variations from the shapes of the illustrations as a result, forexample, of manufacturing techniques and/or tolerances, are to beexpected. Thus, exemplary embodiments disclosed herein should not beconstrued as limited to the particular illustrated shapes of regions,but are to include deviations in shapes that result from, for instance,manufacturing. For example, an implanted region illustrated as arectangle will, typically, have rounded or curved features and/or agradient of implant concentration at its edges rather than a binarychange from implanted to non-implanted region. Likewise, a buried regionformed by implantation may result in some implantation in the regionbetween the buried region and the surface through which the implantationtakes place. Thus, the regions illustrated in the drawings are schematicin nature and their shapes are not intended to illustrate the actualshape of a region of a device and are not intended to be limiting.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure is a part. Terms,such as those defined in commonly used dictionaries, should beinterpreted as having a meaning that is consistent with their meaning inthe context of the relevant art and will not be interpreted in anidealized or overly formal sense, unless expressly so defined herein.

FIG. 1 is a plan view schematically illustrating an organiclight-emitting display apparatus according to an exemplary embodiment.

Referring to FIG. 1, the organic light-emitting display apparatus mayinclude substrate 100, a plurality of thin film transistors (TFTs) onsubstrate 100, a plurality of organic light-emitting diode elements(OLEDs) (P1, P2, and P3) disposed on substrate 100 and connected to theplurality of TFTs, and an insulating layer that includes first wirings310, second wirings 320, third wirings 330, and openings 180 a betweenthe plurality of OLEDs (P1, P2, and P3). An opposite electrode 230 maybe formed on the insulating layer and on an entire surface of a displayarea of the organic light-emitting display apparatus. The display areais an area where an image is displayed, that is, an area other thanedges of the organic light-emitting display apparatus where units suchas controllers are located (non-display area).

The plurality of TFTs and the plurality of OLEDs (P1, P2, and P3) thatare electrically connected to the plurality of TFTs may be disposed onthe display area of the substrate 100. As shown in FIG. 1, each of theplurality of OLEDs may include a red sub-pixel P1, a green sub-pixel P2,and a blue sub-pixel P3. Each pixel unit of the organic light-emittingdisplay apparatus according to the present embodiment includes the redsub-pixel P1, the green sub-pixel P2, and the blue sub-pixel P3.However, in other embodiments of the present inventive concept are notlimited thereto, and the sub-pixels P1, P2, and P3 of the pixel unit maybe arranged in other various colors, in a different order, and thenumbers thereof may vary, for example.

First wirings 310 and second wirings 320 may be formed between at leasta portion of areas between sets of the OLEDs (P1, P2, and P3). Firstwirings 310 and second wirings 320 may be power lines (ELVDD) forsupplying current to the OLEDs, voltage (e.g. low level voltage) lines(ELVSS), or auxiliary wirings. Third wirings 330 may be provided betweenfirst and second wirings 310 and 320 and connect the first and secondwirings 310 and 320. Third wirings 330 may have a smaller width thanwidths of first wirings 310 or widths of the second wirings 320.

According to a direction in which an image is displayed, the organiclight-emitting display apparatus may be a top emission type apparatusthat displays an image in a direction opposite to substrate 100, i.e.,in a direction from substrate 100 to opposite electrode 230, or a bottomemission type apparatus that displays an image toward substrate 100. Thetop emission type apparatus may have a greater opening ratio than thebottom emission type apparatus. When opposite electrode 230 is atransparent electrode in order to display an image toward a top surface,such as an indium tin oxide (ITO) electrode, the transparent electrodemay have a high resistance and an IR drop may occur. Alternatively, whenlow resistance metal, for example, silver (Ag) or magnesium (Mg), isused to form the opposite electrode 230, the opposite electrode 230 hasto be very thin to increase light transmittance and the IR drop may alsooccur due to resistance. The occurrence of the IR drop has become aproblem as a size of the opposite electrode 230 has increased along withthe enlargement of the organic light-emitting display apparatus.

Therefore, in order to manufacture a large, top emission type apparatusand reduce the high resistance of opposite electrode 230, the organiclight-emitting display apparatus according to an exemplary embodimentincludes third wirings 330 connecting first and second wirings 310 and320 arranged at least a portion of areas between sets of the OLEDs, andhaving openings 180 a of the insulating layer that expose third wirings330 and through which opposite electrode 230 contacts third wirings 330.

FIG. 2 is a cross-sectional view illustrating the organic light-emittingdisplay apparatus cut along the lines II-II′ of FIG. 1. FIG. 3 is anenlarged plan view illustrating a portion III of the organiclight-emitting display apparatus of FIG. 1.

Substrate 100 may be formed of various materials, e.g., a glassmaterial, a metal material, or a plastic material, such as polyethyleneterephthalate (PET), polyethylene naphthalate (PEN), or polyimide.Substrate 100 may have a display area where the plurality of OLEDs areformed and a peripheral area around the display area as a non-displayarea.

A TFT may be formed on substrate 100. The TFT includes semiconductorlayer 120 that includes amorphous silicon, polycrystalline silicon, oran organic semiconductor material; gate electrode 140; source electrode160; and drain electrode 162. A general structure of the TFT will bedescribed in detail below.

Buffer layer 110, formed of silicon oxide or silicon nitride, forexample, may be disposed on substrate 100, so as to planarize a surfaceof substrate 100 or to prevent impurities from penetrating intosemiconductor layer 120. The semiconductor layer 120 may be disposed onthe buffer layer 110.

Gate electrode 140 may be disposed on semiconductor layer 120, andsource and drain electrodes 160 and 162 electrically communicate withone another via a signal applied to gate electrode 140. In considerationof adhesion of gate electrode 140 to an adjacent layer, flatness of asurface on which gate electrode 140 is to be stacked, and theprocessability of gate electrode 140, gate electrode 140 may be formedas a single layer or multiple layers. Gate electrode 140 may be formedof at least one material selected from, for example, aluminum (Al),platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au),nickel (Ni), neodymium (Nd), iridium (Ir), chrome (Cr), lithium (Li),calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W), and copper(Cu).

In order to insulate semiconductor layer 120 from gate electrode 140,gate insulating layer 130 formed of the silicon oxide and/or siliconnitride, for example, may be disposed between semiconductor layer 120and gate electrode 140.

Interlayer insulating layer 150 may be disposed on gate electrode 140,and may be formed as a single layer or multiple layers formed of siliconoxide and/or silicon nitride, for example.

Source and drain electrodes 160 and 162 may be disposed on interlayerinsulating layer 150. Source and drain electrodes 160 and 162 may beelectrically connected to semiconductor layer 120 via contact holesformed in interlayer insulating layer 150 and gate insulating layer 130.Regarding the conductivity of source and drain electrodes 160 and 162,source and drain electrodes 160 and 162 may each be formed as a singlelayer or multiple layers. Each of source and drain electrodes 162 and160 may be formed of at least one material selected from, for example,Al, Pt, Pd, Ag, Mg, Au, Ni, Nd, Ir, Cr, Li, Ca, Mo, Ti, W, and Cu.

Although not illustrated in the drawings, a protecting layer may bedisposed to cover the TFT having the above-described structure. Theprotecting layer may be formed of an inorganic material, such as siliconoxide, silicon nitride, or silicon oxynitride.

Planarizing layer 170 may be disposed on the TFT. Planarizing layer 170may be formed of, for example, an acryl-based organic material orbenzocyclobutene (BCB). As illustrated in FIG. 2, buffer layer 110, gateinsulating layer 130, interlayer insulating layer 150, and planarizinglayer 170 may be formed across an entire surface of substrate 100.

Referring to FIG. 2, the TFT and OLED 200 that is electrically connectedto the TFT may be disposed on substrate 100. OLED 200 may include pixelelectrode 210, common layer 215, emission layer (EML) 220, and oppositeelectrode 230.

Pixel electrode 210 may be formed on planarizing layer 170 and may beelectrically connected to drain electrode 162 via a contact hole formedin planarizing layer 170. Pixel electrode 210 may be a reflectiveelectrode and include a reflective layer formed of one selected from Ag,Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, and a combination thereof, and alayer formed of at least one selected from ITO, IZO, ZnO, and In₂O₃ onthe reflective layer. Each sub-pixel of the pixel electrode 210 may bepatterned.

First wiring 310, second wiring 320, and third wiring 330 may bedisposed on planarizing layer 170. First and second wirings 310 and 320may be power lines (ELVDD) for supplying current to OLED 200, voltagelines (ELVSS), or auxiliary wirings. Third wiring 330 may connect firstand second wirings 310 and 320. Since first and second wirings 310 and320 may be formed in an identical process, first and second wirings 310and 320 may be formed on the same layer and include the same material.First and second wirings 310 and 320 may include the same material aspixel electrode 210 and be formed on the same layer as pixel electrode210.

As shown in FIGS. 2 and 3, an end of first wiring 310 and an end ofsecond wiring 320 may be spaced apart. In order to reduce a resistancedeviation between first and second wirings 310 and 320, respectivecross-sections of first and second wirings 310 and 320 may have the samesize. Also, third wiring 330 may include the same material as firstwiring 310, second wiring 320, and pixel electrode 210 and be formed onthe same layer as first wiring 310, second wiring 320, and pixelelectrode 210.

Insulating layer 180 may include first opening 180 b that defines apixel area and second opening 180 a that exposes third wiring 330. Anupper surface of pixel electrode 210 may be exposed via first opening180 b. Third wiring 330, an end of first wiring 310, and an end ofsecond wiring 320 may be exposed via the second opening 180 a.Insulating layer 180 may be formed as, for example, an organicinsulating layer. The organic insulating layer may include one selectedfrom acryl-based polymer (e.g., polymethylmethacrylate (PMMA)),polystyrene (PS), polymer derivatives having a phenol group, imide-basedpolymer, arylether-based polymer, amide-based polymer, fluorine-basedpolymer, p-xylene-based polymer, vinyl alcohol-based polymer, and acombination thereof.

Referring to FIG. 3, third wiring 330, which is exposed through secondopening 180 a of insulating layer 180, may have a zigzag shape or an “S”shape. First wiring 310 may have a first width W1, second wiring 320 mayhave a second width W2, and third wiring 330 may have a third width W3.First width W1 of first wiring 310 may be substantially equal to secondwidth W2 of second wiring 320. Third width W3 of third wiring 330 may besmaller than first width W1 of first wiring 310 and second width W2 ofsecond wiring 320, so that the resistance of third wiring 330 isrelatively higher. Since resistance is inversely proportional to areaand proportional to length, width of third wiring 330 may be reduced toincrease the resistance so that a large amount of Joule heating ismomentarily created. Thus, common layer 215 formed on third wiring 330may be easily removed.

Common layer 215 is formed on pixel electrode 210 that is exposedthrough first opening 180 b and insulating layer 180. Common layer 215may include at least one selected from a hole transport layer (HTL), ahole injection layer (HIL), an electron transport layer (ETL), and anelectron injection layer (EIL). Common layer 215 may be formed on anentire surface of the display area, unlike the EML 220. Although FIG. 2illustrates that common layer 215 is formed first and then EML 220 isformed on the common layer 215, common layer 215 may be formed on EML220.

Common layer 215 may include through hole 215 a that is formed in anarea corresponding to second opening 180 a. Through hole 215 a is anopening through which ends of first and second wirings 310 and 320contact opposite electrode 230. An end of first wiring 310 and an end ofsecond wiring 320, which face third wiring 330, may be exposed throughthrough hole 215 a. Since the end of first wiring 310 and the end ofsecond wiring 320 are spaced apart, at least a portion of an uppersurface of planarizing layer 170 between the respective ends of firstand second wirings 310 and 320 may be exposed through through hole 215a. Similarly, the end of first wiring 310 and the end of second wiring320 that face third wiring 330 may be exposed through second opening 180a of insulating layer 180.

Since through hole 215 a and second opening 180 a are formed indifferent processes, respective sizes of through hole 215 a and secondopening 180 a may be different, as shown in FIGS. 2 and 3. For example,through hole 215 a may be smaller than second opening 180 a.

Since through hole 215 a is formed by heat generated when voltage isapplied to first and second wirings 310 and 320, common layer 215 on anetched surface 180 s of insulating layer 180 may remain. That is, sincethrough hole 215 a is formed by removing a specific area of common layer215 that corresponds to second opening 180 a, an end of common layer 215nearby through hole 215 a may cover etched surface 180 s of insulatinglayer 180. The forming process of through hole 215 a will be describedwith reference to FIGS. 5 through 7.

EML 220 may be disposed on common layer 215. Unlike common layer 215,EML 220 may be formed on pixel electrode 210 that is exposed throughfirst opening 180 b of insulating layer 180. In other words, the HTL,the HIL, the ETL, and the EIL, which may be formed as common layer 215,may be integrally formed on the entire surface of substrate 100, andonly EML 220 may be patterned and formed in each pixel.

EML 220 (emission layer or EML) may include a low molecular weightorganic material or a polymer organic material. When EML 220 includes alow molecular weight organic material, common layer 215 may be disposedaround EML 220. For example, the HTL, the HIL, the ETL, and the EIL maybe stacked. Other various layers may be stacked if necessary. Copperphthalocyanine (CuPc), N′-Di(naphthalene-1-yl)-N, N′-diphenyl-benzidine(NPB), and tris-8-hydroxyquinoline aluminum (Alq₃), may be used as thelow molecular weight organic material.

When EML 220 includes a polymer organic material, the HTL may beincluded as common layer 215, and EML 220 may be disposed on the HTL.The HTL may be formed of poly(3,4-ethylenedioxythiophene) (PEDOT) orpolyaniline (PANI). Poly-phenylenevinylene (PPV)-based andpolyfluorene-based polymer organic material may be used.

Opposite electrode 230 may be disposed on EML 220 and transmit light.Opposite electrode 230 may be formed of a transparent material, forexample, ITO, IZO, ZnO, or In₂O₃. Opposite electrode 230 may contact anend of first wiring 310 and an end of second wiring 320 through throughhole 215 a. Also, opposite electrode 230 may contact upper surface ofplanarizing layer 170 which is exposed through through hole 215 abetween the respective ends of first and second wirings 310 and 320. Asdescribed above, since opposite electrode 230 contacts first and secondwirings 310 and 320, which have a higher electrical conductivity thanopposite electrode 230, opposite electrode 230 may prevent theoccurrence of IR drop.

FIG. 4 is a cross-sectional view illustrating the organic light-emittingdisplay apparatus cut along the lines IV-IV′ of FIG. 3.

As described above, in order to increase the resistance of third wiring330 so that a large amount of Joule heating is created, third width W3of third wiring 330 may be smaller than first width W1 of first wiring310 and second width W2 of second wiring 320, as shown in FIG. 3. At thesame time, as shown in FIG. 4, third height h3 of third wiring 330 maybe adjusted with third width W3 to increase the resistance of thirdwiring 330. First wiring 310 may have first height h1, second wiring 320may have second height h2, and third wiring 330 may have third heighth3. Third height h3 of third wiring 330 may be smaller than first heighth1 of first wiring 310 and second height h2 of second wiring 320.

Accordingly, the resistance of third wiring 330 may be increasedsimultaneously with adjusting third width W3 and the third height h3 ofthird wiring 330. In addition, the resistance of third wiring 330 may beincreased by reducing only third width W3 of third wiring 330 to besmaller than first and second widths W1 and W2 of the first and secondwirings 310 and 320 or by reducing only third height h3 of third wiring330 to be smaller than first and second heights h1 and h2 of first andsecond wirings 310 and 320.

Although the organic light-emitting display apparatus has been mainlydescribed above, the exemplary embodiments are not limited thereto. Amethod of manufacturing the organic light-emitting display apparatus isalso included in the scope of the exemplary embodiments.

FIGS. 5 through 7 are cross-sectional views schematically illustrating amethod of manufacturing the organic light-emitting display apparatus,according to an exemplary embodiment. FIGS. 5 to 7 illustrate anembodiment in which third height h3 of third wiring 330 is equal tofirst and second heights h1 and h2 of first and second wirings 310 and320, and third width W3 of third wiring 330 is smaller than first andsecond widths W1 and W2 of first and second wirings 310 and 320.

FIG. 5 illustrates a process of, after forming the first to thirdwirings 310, 320, and 330, forming insulating layer 180 including secondopening 180 a that exposes the respective ends of first and secondwirings 310 and 320 that face third wiring 330. For convenience ofdescription, it is illustrated that first to third wirings 310, 320, and330 are disposed on substrate 100 in FIGS. 5 through 7. However, variouselements and wirings, such as a TFT or a capacitor, may be disposedbetween substrate 100 and first to third wirings 310, 320, and 330.

Insulating layer 180, which defines a pixel area, may be formed on firstand second wirings 310 and 320. First opening 180 b and second opening180 a may be formed in insulating layer 180. Although first opening 180b is not illustrated in FIGS. 5 through 7, referring to FIGS. 1 through3, first opening 180 b may be formed such that an upper surface of pixelelectrode 210 is exposed to define each of the pixel areas of thedisplay area. Second opening 180 a may be formed such that the first andsecond wirings 310 and 320 are covered and third wiring 330 is exposed.Second opening 180 a may be formed such that respective ends of firstand second wirings 310 and 320 that face the third wiring 330 areexposed. As described above, second opening 180 a may expose thirdwiring 330, and at least a portion of the upper surface of planarizinglayer 170 on which third wiring 330 is formed.

Next, common layer 215 may be formed on the entire surface of thedisplay area to cover insulating layer 180 and third wiring 330 that isexposed through second opening 180 a of insulating layer 180. Commonlayer 215 has been described above.

Referring to FIG. 6, a voltage is applied to first and second wirings310 and 320. Due to the voltage applied to first and second wirings 310and 320, strong heat may be caused in third wiring 330 by Joule heating,and thus the common layer 215 formed on the third wiring 215 may beeasily removed. After the portion of common layer 215 is removed,through hole 215 a may be formed so that the respective ends of firstand second wirings 310 and 320 that face the third wiring 330 areexposed.

Referring to FIG. 7, common layer 215, third wiring 330 exposed throughthrough hole 215 a that is formed by removing at least a portion ofcommon layer 215, and opposite electrode 230, which covers therespective exposed ends of first and second wirings 310 and 320 thatface third wiring 330, may be formed over the entire surface of thedisplay area. Opposite electrode 230 may directly contact third wiring330 through through hole 215 a that is formed by removing at least aportion of common layer 215. As described above, since oppositeelectrode 230 contacts first and second wirings 310 and 320, which havea higher electrical conductivity than opposite electrode 230, oppositeelectrode 230 may prevent the occurrence of an IR drop.

FIG. 8 is a plan view schematically illustrating the display area of theorganic light-emitting display apparatus according to an exemplaryembodiment.

Referring to FIG. 8, substrate 100 may include display areas (DA1, DA2,and DA3), in which pixel units are disposed, and a peripheral area PAthat surrounds the display areas (DA1, DA2, and DA3) as a non-displayarea. The display areas may be respectively referred to as first areaDA1 in the center of substrate 100, second area DA2 that surrounds firstarea DA1, and third area DA3 that surrounds second area DA2. The numberof second openings 180 a formed in first area DA1 per unit area may belarger than the number of second openings 180 a formed in second areaDA2 per unit area, and the number of second openings 180 a formed insecond area DA2 per unit area may be larger than the number of secondopenings 180 a formed in third area DA3 per unit area. Accordingly, whenopposite electrode 230 is formed in one body on substrate 100 that islarge and electric power is supplied from an upper portion and a lowerportion of a panel toward a central portion, an IR drop due to aresistance increase occurs mostly in the central portion of the panel.Therefore, second openings 180 a may be densely formed in the centralportion of the panel where the IR drop mostly occurs and less denselyformed toward outer edges so that the occurrence of the IR drop isprevented in opposite electrode 230 and brightness of the panel isimproved.

As described above, according to the one or more of the above exemplaryembodiments, a large organic light-emitting display apparatus capable ofdisplay high quality images and a method of manufacturing the same aredescribed. However, the scope of the exemplary embodiments is notlimited thereto.

It should be understood that the exemplary embodiments described hereinshould be considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each exemplaryembodiment should typically be considered as available for other similarfeatures or aspects in other exemplary embodiments.

Although certain exemplary embodiments and implementations have beendescribed herein, other embodiments and modifications will be apparentfrom this description. Accordingly, the inventive concept is not limitedto such embodiments, but rather to the broader scope of the presentedclaims and various obvious modifications and equivalent arrangements.

What is claimed is:
 1. An organic light-emitting display apparatuscomprising: a substrate; thin film transistors (TFTs) and organiclight-emitting diode elements(OLEDs) on the substrate, the TFTs beingelectrically connected to the OLEDs; first wirings having a first widthand a first height and second wirings having a second width and a secondheight, wherein the first wirings and the second wirings are formed inat least a portion of areas between the OLEDs; third wirings connectingthe first wirings and the second wirings and having a third widthsmaller than the first width of the first wirings and the second widthof the second wirings or having a third height smaller than the firstheight of the first wirings and the second height of the second wirings;and an insulating layer covering at least a portion of the first wiringsand the second wirings and comprising openings that expose the thirdwirings.
 2. The apparatus of claim 1, wherein each of the third wiringscomprises a zigzag shape or an “S” shape.
 3. The apparatus of claim 2,wherein the OLEDs comprise: pixel electrodes; emission layers patternedcorresponding to the pixel electrodes and formed on the pixelelectrodes; an opposite electrode facing the pixel electrodes; and acommon layer between the pixel electrodes and the opposite electrode andformed in one body on the pixel electrodes, wherein the common layercomprises through holes that correspond to the area including the thirdwirings exposed by the openings.
 4. The apparatus of claim 3, whereinthe third wirings exposed by the openings directly contact the oppositeelectrode.
 5. The apparatus of claim 3, wherein the first wirings, thesecond wirings, the third wirings, and the pixel electrodes comprise thesame material and are formed on the same layer.
 6. The apparatus ofclaim 3, wherein the openings in the insulating layer expose respectiveends of the first and second wirings which face the third wirings. 7.The apparatus of claim 3, wherein the through holes in the common layerexpose respective ends of the first and second wirings which face thethird wirings.
 8. The apparatus of claim 1, wherein the third width ofthe third wirings is smaller than the first width of the first wiringsand the second width of the second wirings, and the third height of thethird wirings is smaller than the first height of the first wirings andthe second height of the second wirings.
 9. The apparatus of claim 1,wherein the substrate comprises a first area in a center of thesubstrate, a second area that surrounds the first area, and a third areathat surrounds the second area, and the number of openings formed in thefirst area per unit area is the largest among the all areas.
 10. Theapparatus of claim 9, wherein the number of openings disposed in thefirst area per unit area is larger than the number of openings disposedin the second area per unit area, and the number of openings disposed inthe second area per unit area is larger than the number of secondopenings disposed in the third area per unit area.
 11. An organiclight-emitting display apparatus comprising: a substrate; a first thinfilm transistor (TFT) and a first organic light-emitting diode element(OLED) on the substrate, the first TFT being electrically connected tothe first OLED; a second TFT and a second OLED on the substrate, thesecond TFT being electrically connected to the second OLED; a third TFTand a third OLED on the substrate, the third TFT being electricallyconnected to the third OLED; a first wiring having a first width and afirst height, wherein the first wiring is disposed in at least a portionof an area between the first and second OLEDs; a second wiring having asecond width and a second height, wherein the second wiring is disposedin at least a portion of an area between the second and third OLEDs; athird wiring connecting the first wiring and the second wiring andhaving at least one of (a) a third width smaller than the first width ofthe first wiring and the second width of the is second wiring and (b) athird height smaller than the first height of the first wiring and thesecond height of the second wiring; and an insulating layer covering atleast a portion of the first wiring and the second wiring and comprisingan opening that exposes at least a portion of the third wiring.
 12. Amethod of manufacturing an organic light-emitting display apparatus, themethod comprising: preparing a substrate; forming pixel electrodes onthe substrate; forming first wirings between at least a portion of thepixel electrodes, the first wirings having a first width and a firstheight; forming second wirings between at least a portion of the pixelelectrodes and between at least a portion of the first wirings, thesecond wirings having a second width and a second height; forming thirdwirings connecting respective first and second wirings and having atleast one of (a) a third width smaller than the first width of therespective first wiring and the second width of the respective secondwiring and (b) a third height smaller than the first height of therespective first wiring and the second height of the respective secondwiring; forming an insulating layer comprising first openings to exposeat least a central portion of respective pixel electrodes and secondopenings to expose at least a portion of the third is wirings; forming acommon layer across the surface of the insulating layer and on theexposed portions of the pixel electrodes in the first openings and theexposed portions of the third wirings in the second openings; removingportions of the common layer disposed on the exposed portions of thethird wirings in the second openings by applying a voltage to the firstand second wirings; and forming an opposite electrode on the commonlayer such that the opposite electrode directly contacts the exposedportions of the third wirings.
 13. The method of claim 12, wherein theinsulating layer covers the pixel electrodes such that central portionsof the pixel electrodes are exposed.
 14. The method of claim 12, whereinthe insulating layer covers at least a portion of the first wirings andthe second wirings.
 15. The method of claim 12, wherein the thirdwirings comprise a zigzag shape or an “S” shape.
 16. The method of claim12, further comprising the step of patterning emission layers on thepixel electrodes, which are exposed through the first openings in theinsulating layer, such that the emission layers correspond to the pixelelectrodes.
 17. The method of claim 12, wherein the third wirings havethe third width smaller than the first width of the respective firstwirings and the second width of the respective second wirings, and havethe third height smaller than the first height of the respective firstwirings and the second height of the respective second wirings.
 18. Themethod of claim 12, wherein the steps of the forming of the pixelelectrodes, the forming of the first and second wirings, and the formingof the third wirings are simultaneously executed.
 19. The method ofclaim 12, wherein the substrate comprises a first area in a center ofthe substrate, a second area that surrounds the first area, and a thirdarea that surrounds the second area, and the number of the secondopenings disposed in the first area per unit area is the largest amongthe first, second, and third areas.
 20. The method of claim 19, whereinthe number of second openings disposed in the first area per unit areais larger than the number of second openings disposed in the second areaper unit area, and the number of second openings disposed in the secondarea per unit area is larger than the number of second openings disposedin the third area per unit area.